pNFS/flexfiles: When initing reads or writes, we might have to retry connecting to...

If we are initializing reads or writes and can not connect to a DS, then
check whether or not IO is allowed through the MDS. If it is allowed,
reset to the MDS. Else, fail the layout segment and force a retry
of a new layout segment.

Signed-off-by: Tom Haynes <loghyr@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

diff --git a/fs/nfs/flexfilelayout/flexfilelayout.c b/fs/nfs/flexfilelayout/flexfilelayout.c
index a835b75f85ab6383f200001e9607a203e41aad33..2911ceda8cd92288fe46960d0f7ac3bca74895f7 100644 (file)
--- a/fs/nfs/flexfilelayout/flexfilelayout.c
+++ b/fs/nfs/flexfilelayout/flexfilelayout.c
@@ -848,8 +848,13 @@ ff_layout_pg_init_read(struct nfs_pageio_descriptor *pgio,
                goto out_mds;
 
        ds = ff_layout_choose_best_ds_for_read(pgio->pg_lseg, 0, &ds_idx);
-       if (!ds)
-               goto out_mds;
+       if (!ds) {
+               if (ff_layout_no_fallback_to_mds(pgio->pg_lseg))
+                       goto out_pnfs;
+               else
+                       goto out_mds;
+       }
+
        mirror = FF_LAYOUT_COMP(pgio->pg_lseg, ds_idx);
 
        pgio->pg_mirror_idx = ds_idx;
@@ -863,6 +868,12 @@ out_mds:
        pnfs_put_lseg(pgio->pg_lseg);
        pgio->pg_lseg = NULL;
        nfs_pageio_reset_read_mds(pgio);
+       return;
+
+out_pnfs:
+       pnfs_set_lo_fail(pgio->pg_lseg);
+       pnfs_put_lseg(pgio->pg_lseg);
+       pgio->pg_lseg = NULL;
 }
 
 static void
@@ -905,8 +916,12 @@ ff_layout_pg_init_write(struct nfs_pageio_descriptor *pgio,
 
        for (i = 0; i < pgio->pg_mirror_count; i++) {
                ds = nfs4_ff_layout_prepare_ds(pgio->pg_lseg, i, true);
-               if (!ds)
-                       goto out_mds;
+               if (!ds) {
+                       if (ff_layout_no_fallback_to_mds(pgio->pg_lseg))
+                               goto out_pnfs;
+                       else
+                               goto out_mds;
+               }
                pgm = &pgio->pg_mirrors[i];
                mirror = FF_LAYOUT_COMP(pgio->pg_lseg, i);
                pgm->pg_bsize = mirror->mirror_ds->ds_versions[0].wsize;
@@ -918,6 +933,12 @@ out_mds:
        pnfs_put_lseg(pgio->pg_lseg);
        pgio->pg_lseg = NULL;
        nfs_pageio_reset_write_mds(pgio);
+       return;
+
+out_pnfs:
+       pnfs_set_lo_fail(pgio->pg_lseg);
+       pnfs_put_lseg(pgio->pg_lseg);
+       pgio->pg_lseg = NULL;
 }
 
 static unsigned int